JPH08336069A - Electronic still camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To output a still image in correct direction by automatically detecting the direction of camera to an object, without special application programs. SOLUTION: This electronic still camera is provided with an electronic image- pickup sensor 16 for generating an image signal, corresponding to the still image of an object and a direction decision part 36 for detecting the direction of camera to the object. The direction decision part 36 generates a direction signal for recognizing whether the camera is vertical or horizontal with respect to the object. In response to the direction signal, an image processor 22 processes the image signal and corrects its direction, so that the still image can be outputted from the image processor 22 in prescribed direction. Thus, the electronic still camera 10 can be positioned in various directions with respect to the object, while including a horizontal scenery direction and both clockwise and counterclockwise vertical figure directions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of electronic still photography, and more particularly to a hand-held electronic still camera capable of holding an object in various orientations.

[0002]

2. Description of the Related Art In a conventional video camera such as an 8 mm camcorder for displaying an image on a television screen, when trying to obtain an image oriented in a normal direction, the camera is horizontally or horizontally (so-called "landscape").
Direction, hereinafter simply referred to as landscape direction). When the camera is rotated vertically (so-called “person” direction, hereinafter simply referred to as “person direction”), the image displayed on the television screen also rotates according to the rotation of the camera. If the display screen is rotated or the viewer changes the direction the screen is viewed, the image will not rotate, which is not practical for a television. This rotation of the image is a serious problem in practical use. This is because the rotation toward the person actually has two directions: clockwise rotation and counterclockwise rotation. Therefore, as shown in FIG. 1, the sky appears not on the upper part of the screen but on the left or right side of the screen in each of the two person directions. In conventional photography with film, the film camera could be rotated in any direction. Therefore, when looking at a picture taken with a vertical person camera, the picture is rotated, and in the case of a slide, the direction of the slide is also rotated in the projector.

On the other hand, in the latest electronic still cameras such as Kodak DC40 camera (sold by Eastman Kodak Company), the user can display the photographed still image on the computer screen. Similar to film-based cameras, such electronic cameras can be easily rotated so that the image can be oriented either in a horizontal landscape direction or in two vertical portrait orientations. However, the first image that appears on the computer screen always assumes the camera is in a horizontal position. For this reason, any images taken with a camera facing the person are rotating and the sky (should be at the top of the image)
Is on the left or right, not the top of the statue. Some computer image processing software includes Adobe Photoshop
Some have a function to rotate the image stored in the computer in the correct direction, such as hop (trademark) (sold by Adobe Inc.).
One has to manually perform the tedious operation of selecting each one and rotating each clockwise or counterclockwise.

Also, a special automatic turning function called "album application" is provided in US Pat. No. 5,27.
No. 4,418. This still video camera shoots a plurality of images together with control information and edits those images like one page of an album. The camera is equipped with a direction detector that marks the direction of the output medium, and is necessary for a separately provided player to read this direction data and display the image properly arranged as one page of an album. Adjust the image according to. This imaging system requires a special application program in the player, and direction correction can only be done with that special player. In other words, the direction change is performed "automatically" only when using a special application program in this special player.

There is another type of image processing method that corrects for unwanted camera tilt. As an example, US Pat. No. 5,
The video camera as described in No. 227,889 detects and corrects the vertical tilt amount of the entire camera when the camera is tilted, for example, for shooting while walking. The tilt is corrected by controlling the addressing of the two field memories based on the tilt information and correcting the tilt of the output moving image signal in real time. Thus the undesired camera orientation is corrected in the output signal. However, a sudden tilt correction is necessary in the case of a video camera for motion pictures, but with a still camera, you intentionally take a tilted picture when you want to add all the desired details to the finished still picture. In many cases, if the tilt of the camera is continuously corrected as described above, this cannot be done. In other words, the problem is not how to control undesired situations such as image tilt, but how to operate in desired situations such as person orientation.
And how to properly correct the situation.

[0006]

As described above, in the electronic still camel capable of positioning in various directions including the portrait direction vertical to the subject and the horizontal landscape direction, the conventional electronic still camera has a special application. It was not possible to output the image in the correct orientation by automatically detecting the orientation of the camera with respect to the subject and correcting the orientation of the image without using a program.

[0007]

In order to solve these problems in accordance with the disclosure of the present invention, an electronic image sensor for generating an image signal corresponding to a still image of a subject, and a direction for detecting the orientation of the camera with respect to the subject. An electronic still camera including a determination unit is provided. The direction determination unit generates a direction signal indicating at least a vertical direction of the orientation with respect to the subject. An image processor in the camera processes the image signal in response to the direction signal and modifies the direction of the image signal so that a still image in a predetermined direction is output from the camera.

More specifically, electronic still cameras include a pair of directional sensors, such as mercury switches. This direction sensor determines whether the user holds the camera in the normal horizontal landscape direction or in the vertical person direction during shooting. The image rotates inside the camera and is always stored in the same orientation (ie horizontal).

These and other objects, features and advantages of the present invention will be more clearly understood with reference to the following claims, and the following detailed description of the preferred embodiments, and the accompanying drawings. I think I can do it.

[0010]

2 is a block diagram of an electronic camera 10 using an automatic direction correcting function according to the present invention. This camera is usually a handheld device that forms an image of an object 14 on a charge-coupled device (hereinafter referred to as CCD) image sensor 16. The sensor 16 is a CCD driver circuit 18
Clocked by to generate an analog image signal corresponding to a still image of the subject. This analog image signal is converted into a digital image signal by the A / D converter 20. To control the exposure time, the aperture of the lens 12 is adjusted by the conventional diaphragm 23, and the CCD driver circuit 18 is used.
Is performed using the conventional electronic shutter of the image sensor 16. (A mechanical shutter (not shown) may be used in place of the electronic shutter.) The digital image signal is processed by the image processor 22 and has a removable solid state having a plurality of memories for storing processed digital image. It is stored in a digital memory such as the memory card 24. As the CCD image sensor 16, a CCD sensor such as Kodak model KAF-0400C having 512 light receiving elements (768 light receiving elements per one) is used. In this KAF-0400C CCD sensor, the intervals between the light receiving elements in the vertical and horizontal directions are both 9
Since it is micron, the pixel is square and has a horizontal aspect ratio of 3: 2.

The memory card 24 is "PC Card Standard 2.0 Edition" (September 1991, Personal Computer Memory Card International Association, published at Sanny Vale, CA, USA).
It is preferably constructed according to the well-known PCMCIA card interface standard described in. This standard defines the interface pin assignments for coupling the memory card 24 to the camera 10 via the PCMCIA interface 26. Memory card 24
Can be removed from the camera 10 by moving it away from the interface 26. The removed card 24 is the same PCM
It can be inserted into the computer 28 via the CIA interface 30. Then, the central processing unit 32 in the computer 28 reads the image signal from the memory card 24 and sends the image signal to the display 34 to display the image on the computer system. Alternatively, a solid-state memory corresponding to the memory card 24 may be attached inside the camera and the camera itself may be connected to an interface cable (not shown) to download and display an image. In both cases, the image is displayed in the correct orientation so that it looks correct.

In one embodiment of the present invention, the camera includes a direction determining section 36. The direction determination unit 36 determines whether the camera is oriented in the horizontal landscape direction or the first (clockwise) or second (counterclockwise) vertical person direction. (As will be described in detail with reference to FIG. 9, the direction determination unit 36 can also determine that the camera is held in an upside down inverted horizontal position.) The direction determination unit 36 includes one or more direction sensors 40 and an object. And a logic unit 42 for generating a direction signal indicating the orientation of the camera. The direction signal is sent to the camera control interface 38. The direction signal indicates at least that the camera is oriented vertically. (Thus, the absence of this signal indicates a horizontal orientation.) Or, it may positively indicate whether the camera is vertical or horizontal. The camera control interface 38, when signaled by the shutter button 44, commands the CCD driver 18 to clock the image signal from the sensor 16. At the same time, the interface 38 uses the direction determination unit 3
6 provides a direction signal to the image processor 22. The image processor 22 processes the image signal in response to the direction signal and corrects the direction of the image signal to output a still image from the image processor 22 in a predetermined orientation and store it in the memory card 24, after which The image is displayed on the display 34. Normally, this predetermined orientation is common to all images, and the image processor 22 transforms the vertical image into the horizontal image. Note that the image is 512 (V) x 768 (H) in the landscape direction, but the image stored in the person direction is 768 (V) x 512.
(H).

FIG. 8 schematically shows a signal processing architecture for determining the rotation of an image. This architecture can be incorporated into the image processor 22 as hardware or software. A / D converter 20
The data read from the memory is read through a random access buffer memory (hereinafter referred to as RAM) 52 via an input bus 50.
RAM 52 is connected to at least one image (51
2 × 768 pixels). The direction signal is coupled to the memory read controller 56 via the control bus 54. This controller 56 may be a part of the controller microprocessor 57 in the image processor 22 programmed, or may be a separate dedicated controller that is driven by the microprocessor 57 to control the generation of read address and clock signals to the memory 52. May be a combinational logic unit of The address and clock signals are provided via address bus links 58 and 60 to an associated set of row address counters 62 and column address counters 64 to control the access rate and order of access to the contents of memory 52. To do. In particular, the clock signal lines increment (if the up / down signal is asserted) or decrement (if the up / down signal is not asserted) counters 62 and 64. US Pat. No. 5,270,831 (Title of Invention "Method of storing and playing digitized image in digital database with display control file to define orientation and aspect ratio of image") is here A signal processing architecture is described that automatically uses a direction code similar to that described. The contents of this patent are hereby incorporated by reference.

The memory controller 56 changes the orientation of the image in the memory 52 by controlling the readout of the pixel raster as shown in FIG. Memory writing map 6
Reference numeral 6 indicates data directly acquired from the sensor 16 regardless of the direction. If the camera is horizontal, the horizontal read map 68 is the same as the memory write map 66, but if the camera is oriented vertically clockwise or counterclockwise, the memory controller 56 will cause the memory 52
In the vertical (clockwise) memory read map 70, from the lower left, the vertical (counterclockwise) memory read map 72
Then, read from the upper right one by one. FIG. 9 also shows an anti-horizontal image, i.e. the image obtained when the camera 10 is held horizontally but upside down. In this case, the inverse memory read map 74 is just the reverse of the horizontal memory read map 68. (However, since such a reverse position often happens not intentionally but accidentally, the camera 10 is equipped with a lockout or a warning mechanism (not shown) in case the camera is turned upside down. FIG. 7 shows an embodiment of the direction sensor 40. The camera 10 has two switches 8 filled with mercury.
2, 84 are mounted one vertically and one horizontally. Switches 82, 84 include a first switch contact pair 86 and a second switch contact pair 88,
A conductive mercury bubble 90 is trapped between the first and second switch contacts. This conductive mercury bubble 90
2 of either of the two direction sensors 82, 84
Gravity acts to close one of the two switch contacts 86, 88 and the switch contacts 86, 88 of the other direction sensor are both open. Thus, the three switches are always open so that the signal becomes + V level (that is, high level), and at the same time, one switch is closed so that the signal becomes low level (that is, ground level). Therefore, the direction of the camera can be determined by knowing which signal is at the low level. For example, if the switch contact 88 of the switch 82 is closed, the camera 10 is held in the horizontal position, and if either switch contact 86 or 88 of the switch 84 is closed, there are two cameras 10. It is held in one of the positions, and so on. The output of the switch is given to the logic unit 42, where the switch signal is converted into a direction code such as 00 = horizontal, 01 = vertical (clockwise), 10 = vertical (counterclockwise).

FIG. 7 illustrates the concept of a direction sensor, and in practice it is preferred that mercury is not used in at least some applications. It is also possible to use a photo interrupter type switch. In this type of switch, for example, a light emitter and a detector are provided at both ends of the camera in order to detect two person directions, and a sphere that blocks light according to the direction of the camera is dragged along a groove.
Alternatively, for example, a weighted light-shielding wheel may be provided and rotated between one light emitter and two detectors attached to the camera body. The wheels are provided with light transmissive grooves so that both detectors are blocked in the landscape direction and one detector is blocked in each person direction.

FIG. 3 shows a method of operating the camera of the present invention. When the user presses the shutter button 44 to take an image, the sensor 16 is exposed and the image is read, and the direction determination unit 36 determines the orientation of the camera 10 while the image is read from the sensor 16. If orientation correction is required, the image processor 22 rotates the image data,
The rotated image data is stored in the memory card 24 in the correct orientation (see FIG. 4). 5 and 6 show another scanning method of the camera. Here, when the image data is written to the RAM memory 52, the direction code of the camera is stored in the header together with each image. At this stage, each image is still 512 (V) x 768 (H), and the direction code displays this image in the normal landscape mode (00) or the person direction No. When the image is taken at No. 1 (01), the image is rotated clockwise and displayed, or the person direction No. When the image is captured at 2 (10), it is displayed by rotating it counterclockwise. Each image is RAM
Once read from 52, processor 57 inspects the orientation code and rotates the image if necessary depending on the orientation of the camera. Thus, each image is stored in the memory card 24 in the correct orientation as shown in FIG. An advantage of this embodiment of storing the orientation code in the header is that multiple images with headers can be obtained and stored in the buffer memory 52 before the processor 57 begins rotating the images. This makes it easier to operate in burst mode,
You can quickly take multiple images. Also, the above-mentioned US Pat. No. 5,270,831 discloses a signal processing architecture for use in a processor that decodes direction information in an image header when processing an acquired image. In this architecture, images are stored on a memory card in an upright orientation and with the correct aspect ratio for later display on a screen by a computer.

Further, as shown in FIG. 6, the direction code can be stored in the memory card 24 together with the image of the correct orientation. The stored direction code may be useful when the memory card 24 is transferred to the computer 28 and the computer 28 performs image processing. For example, image processing for exposure control may be performed according to the orientation of the image, or the aspect ratio of the image may be reconfigured by a code to obtain an effect such as a portrait with a border area. You can also The camera may also be provided with a direction on / off switch 36 'to store uncorrected images in a memory card. In this case, the orientation correction is done only by the computer. However, if all the images are to be modified inside the camera, the switch 36 'can be set on and the camera operated according to the flow diagram shown in FIG. In this embodiment, the image is always rotated as needed, and the original orientation record is not saved in the header (except in the case of the orientation code storage embodiment described above).

Although the present invention has been described above with reference to the preferred embodiments, those skilled in the art will recognize that variations and modifications can be made without departing from the scope of the present invention.

[0019]

The main advantage of the present invention is that since the image is rotated inside the camera so that the stored image always faces the right direction, the image can be displayed on a player or computer screen without using a special application program. That is what can be displayed correctly above.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a state of the art in which an image in a vertical person direction is shown in a wrong orientation on a display screen.

FIG. 2 is a block diagram of an imaging system including an electronic still camera having a direction correcting function according to the present invention.

FIG. 3 is a flowchart showing the operation of the camera according to the present invention.

FIG. 4 shows an image stored in the correct orientation in accordance with the present invention.

FIG. 5 is a flowchart showing another operation of the camera of the present invention.

FIG. 6 is a diagram showing an image stored according to another operation shown in FIG.

7 is a diagram showing an embodiment of a direction sensor used in the camera shown in FIG.

FIG. 8 illustrates an embodiment of a signal processing architecture for determining image rotation.

FIG. 9 is a diagram showing how the architecture of FIG. 8 is used to read a buffer memory for various directions.

[Explanation of symbols]

10 electronic camera, 12 lens, 14 subject, 16
CCD image sensor, 18 CCD driver circuit, 20
A / D converter, 22 image processor, 24 removable solid-state memory card, 26, 30 PCMCIA interface, 28 computer, 32 central processing unit, 34 display, 36 direction determination unit, 38 camera control interface, 40 direction sensor, 42 logic Section, 44 shutter button, 50 input bus, 52
RAM buffer memory, 54 control bus, 56 memory read controller, 57 controller microprocessor, 58, 60 address bus link, 62
Row address counter, 64 column address counter, 66
Memory write map, 68 horizontal memory read map, 70 vertical (clockwise) memory read map,
72 vertical (counterclockwise) memory read map, 74
Inverted memory readout map, 82,84 mercury switch, 86,88 switch contact, 90 mercury.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Harumi Omori 4-11-9 Shimouma, Setagaya-ku, Tokyo (72) Inventor Masaki Izumi 1-12-8 Ryoke, Izumi-ku, Yokohama-shi, Kanagawa (72) Inventor Mizukoshi Seiichi 8-32 Motomachi, Chigasaki City, Kanagawa Prefecture

Claims (5)

[Claims] 1. An electronic still camera capable of being positioned in various directions including a person direction vertical to a subject and a horizontal landscape direction, wherein an image signal corresponding to a still image of the subject is generated. An electronic image sensor that generates, a direction determination unit that detects a direction of the camera with respect to the subject and generates a direction signal indicating at least the vertical direction of the camera with respect to the subject, and the image signal in response to the direction signal. An image processor for processing and correcting the direction of the image signal so that the still image is output in a predetermined orientation. 2. The camera according to claim 1, wherein the direction determination unit indicates the horizontal direction in addition to the vertical direction with respect to the subject. 3. The camera according to claim 1, wherein the direction determination unit includes a direction sensor that responds to the vertical direction and the horizontal direction of the camera. 4. The camera according to claim 3, wherein the direction determination unit includes a logic unit that is responsive to the direction sensor to generate a direction code having a plurality of values indicating the plurality of directions. Characteristic camera. 5. The camera according to claim 1, wherein the image processor includes a buffer memory for storing the image signal and a memory controller for addressing the buffer memory, whereby a non-horizontal direction is provided. Means that the memory is read out in an order different from the order in which the addresses are written, and the addresses are changed between a read cycle and a write cycle so that the image is always output from the image processor in the predetermined orientation. Characteristic camera.